This youth hostel was pretty good. We may have been upgraded from a twin to a triple, so the room seemed nice, quiet, clean and big for just two of us, given it even had a table and chairs and lockers within the room. Breakfast was also decent, and included in the price, which is always a good thing.
The main thing I didn't like was that check-out time was 9 a.m., so, leaving Salzburg at 1 in the afternoon meant that we had to leave our luggage downstairs in an unlocked room for a few hours. Also, the lift is for staff only, so we had to drag our bags up four floors.
In terms of meeting new people, aside from the breakfast room and a small game room in the basement near the laundry (which I didn't notice till we were leaving), there are very few communal rooms. The TV room upstairs doesn't really work very well for meeting people since everyone's focussed on the box. So if you're after socializing with new people, this probably isn't the place to go. But it worked well as a place to just crash, get a good night's sleep and a decent breakfast.